Indonesia is the home to more than twenty million hectares of peat-land and swamp, distributed in three major islands of Sumatera, Kalimantan, and Papua. Indonesia has the largest tropical peat swamp in the world. The areas are covered with mixed forests, secondary forests of logged over areas, shrubs, seagrass, marsh grass, mangroves as well as heavily degraded peat-lands. Degraded peat lands on Sumatera and Kalimantan alone span over three million hectares. More than seventy percent of the peat land in Sumatera and Kalimantan are developed on mineral soils layers which are located below the current sea level and when drained will be lost to flooding due to subsidence – the gradual sinking of the peat-land.